Proton Therapy

Has anyone heard of proton therapy? Our two largest hospitals here (St Louis County) are opening cancer treating centers for proton therapy, The news item says other proton treating centers have had problems but that we will now have two here "despite" that.

I have a friend whose child was diagnosed with a brain tumor, and proton therapy was offered and they took it. I think they use protons as radiation in an attempt to kill the cancer. I would never advise a child to undergo this as I have seen the long term effects. It stunts growth and so there should be more humane ways to treat children with such cancers.

Has anyone heard of proton therapy? Our two largest hospitals here (St Louis County) are opening cancer treating centers for proton therapy, The news item says other proton treating centers have had problems but that we will now have two here "despite" that.

What is proton therapy?

It's a kind of radiotherapy using protons instead of radiation from radioisotopes. The advantage of it is that charged particles such as protons lose energy only slowly as they pass through tissue until they are slowed down to a certain speed, at which point they give up energy much faster and stop. So by tuning the energy of a proton beam, the radiotherapist can arrange for most of the energy, i.e. most of the genetic damage to cells, to occur at the site of the tumour, not before reaching it and not after passing through it. So it allows for more precision and less "collateral damage" to healthy tissue on the way.

The downside of it is you need a cyclotron or something to accelerate the protons, which is an expensive piece of kit.

It's a kind of radiotherapy using protons instead of radiation from radioisotopes. The advantage of it is that charged particles such as protons lose energy only slowly as they pass through tissue until they are slowed down to a certain speed, at which point they give up energy much faster and stop. So by tuning the energy of a proton beam, the radiotherapist can arrange for most of the energy, i.e. most of the genetic damage to cells, to occur at the site of the tumour, not before reaching it and not after passing through it. So it allows for more precision and less "collateral damage" to healthy tissue on the way.

The downside of it is you need a cyclotron or something to accelerate the protons, which is an expensive piece of kit.

Thank you both for the explanation and comment. From what you say, exchemist, I see it as an attempt to zero in on the exact area that is wanted. Perhaps a very powerful radiation machine? I'm not sure why we are using radiation on the human body but that's something I can look up. Thanks.

They use radiation because it's a very directed way to cause tissue damage. When it comes to cancer, you have to realize that cancer cells are generally harder to kill than healthy cells. Most Chemotherapy exploits cancer's high metabolism with "poison food" to have the cancer build up deadly levels of toxins faster than the regular cells, but that becomes a careful game of balancing total toxins in the body vs the concentrated stuff.

With Radiotherapy they use some other more direct methods. The proton method is like how others described. Other radio therapy usees multiple beams from several angles to "overlap" each other meaning one area gets 2 or more beams of radiation saturating it with high levels while surrounding tissue takes less.

As with most medical systems, a good portion of the danger is the human operating it: does the tech know how to math, and did they RTFM? Sometimes, they don't.

All in all it's a game of trying to deathray a very specific part of a human while leaving the other parts alone.

Thank you both for the explanation and comment. From what you say, exchemist, I see it as an attempt to zero in on the exact area that is wanted. Perhaps a very powerful radiation machine? I'm not sure why we are using radiation on the human body but that's something I can look up. Thanks.

Yes exactly, an attempt to zero in on an exact volume, the problem generally being that in zapping deep-seated tissue, any beam will tend to damage tissues along its path to the cancer as well.

Radiation works by being "ionising". When it is absorbed it knocks electrons off atoms and makes ions. Cancer cells differ from normal cells in the body by dividing at a rapid and uncontrolled rate. This means that their DNA is being continually copied at a furious rate, to make new cancer cells. Ions created by radiation mess up the DNA of the cell, preventing the division into new cells from taking place accurately and inhibiting the growth of the cancer.